.\"
.\" Copyright (c) 2004 Max Laier <mlaier@FreeBSD.org>
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd January 21, 2024
.Dt ALTQ 4
.Os
.Sh NAME
.Nm ALTQ
.Nd "alternate queuing of network packets"
.Sh SYNOPSIS
.Cd options ALTQ
.Pp
.Cd options ALTQ_CBQ
.Cd options ALTQ_CODEL
.Cd options ALTQ_RED
.Cd options ALTQ_RIO
.Cd options ALTQ_HFSC
.Cd options ALTQ_CDNR
.Cd options ALTQ_PRIQ
.Cd options ALTQ_FAIRQ
.Sh DESCRIPTION
The
.Nm
system is a framework which provides several disciplines for queuing outgoing
network packets.
This is done by modifications to the interface packet queues.
See
.Xr altq 9
for details.
.Pp
The user interface for
.Nm
is implemented by the
.Xr pfctl 8
utility, so please refer to the
.Xr pfctl 8
and the
.Xr pf.conf 5
man pages for a complete description of the
.Nm
capabilities and how to use it.
.Ss Kernel Options
The following options in the kernel configuration file are related to
.Nm
operation:
.Pp
.Bl -tag -width ".Dv ALTQ_DEBUG" -compact
.It Dv ALTQ
Enable
.Nm .
.It Dv ALTQ_CBQ
Build the
.Dq "Class Based Queuing"
discipline.
.It Dv ALTQ_CODEL
Build the
.Dq "Controlled Delay"
discipline.
.It Dv ALTQ_RED
Build the
.Dq "Random Early Detection"
extension.
.It Dv ALTQ_RIO
Build
.Dq "Random Early Drop"
for input and output.
.It Dv ALTQ_HFSC
Build the
.Dq "Hierarchical Packet Scheduler"
discipline.
.It Dv ALTQ_CDNR
Build the traffic conditioner.
This option is meaningless at the moment as the conditioner is not used by
any of the available disciplines or consumers.
.It Dv ALTQ_PRIQ
Build the
.Dq "Priority Queuing"
discipline.
.It Dv ALTQ_FAIRQ
Build the
.Dq "Fair Queuing"
discipline.
.It Dv ALTQ_NOPCC
Required if the TSC is unusable.
.It Dv ALTQ_DEBUG
Enable additional debugging facilities.
.El
.Pp
Note that
.Nm Ns -disciplines
cannot be loaded as kernel modules.
In order to use a certain discipline you have to build it into a custom
kernel.
The
.Xr pf 4
interface, that is required for the configuration process of
.Nm
can be loaded as a module.
.Sh SUPPORTED DEVICES
The driver modifications described in
.Xr altq 9
are required to use a certain network card with
.Nm .
They have been applied to the following hardware drivers:
.Xr ae 4 ,
.Xr age 4 ,
.Xr alc 4 ,
.Xr ale 4 ,
.Xr aue 4 ,
.Xr axe 4 ,
.Xr bce 4 ,
.Xr bfe 4 ,
.Xr bge 4 ,
.Xr bxe 4 ,
.Xr cas 4 ,
.Xr dc 4 ,
.Xr em 4 ,
.Xr epair 4 ,
.Xr et 4 ,
.Xr fxp 4 ,
.Xr gem 4 ,
.Xr igb 4 ,
.Xr ix 4 ,
.Xr jme 4 ,
.Xr le 4 ,
.Xr liquidio 4 ,
.Xr msk 4 ,
.Xr mxge 4 ,
.Xr my 4 ,
.Xr nfe 4 ,
.Xr nge 4 ,
.Xr qlxgb 4 ,
.Xr re 4 ,
.Xr rl 4 ,
.Xr sge 4 ,
.Xr sis 4 ,
.Xr sk 4 ,
.Xr ste 4 ,
.Xr stge 4 ,
.Xr ti 4 ,
.Xr udav 4 ,
.Xr vge 4 ,
.Xr vr 4 ,
.Xr vte 4 ,
and
.Xr xl 4 .
.Pp
The
.Xr tun 4 ,
.Xr if_bridge 4 ,
.Xr if_vlan 4 ,
and
.Xr ng_iface 4
pseudo drivers also do support
.Nm .
.Pp
An example:
.Bd -literal -offset indent
altq on igb0 cbq queue { def aq }
queue def bandwidth 90% cbq (default borrow)
queue aq bandwidth 10Mb cbq

pass in on igb0.10 proto udp all queue aq keep state
.Ed
.Sh SEE ALSO
.Xr pf 4 ,
.Xr pf.conf 5 ,
.Xr ipfw 8 ,
.Xr pfctl 8 ,
.Xr altq 9
.Sh HISTORY
The
.Nm
system first appeared in March 1997 and found home in the KAME project
(https://www.kame.net).
It was imported to
.Fx
in 5.3 .
